Ahh the Orochi Isles. Land of those with true power and the ability to execute it with nigh supernatural effectiveness.
But alas it wasn't always that way.
The Islands were at one point completely overwhelmed by monstrosities. Until the fabled Kochu Torrikkusatu discovered how to access the untapped power of Ether.
You see there has always been two sources of power in Rexia.
Mana which is constantly being produced by the earth and acts as it's unending life force.
And Ether the life force of all beings who live in Rexia, and is naturally produced within them.
After Torrikkusatu's development he was able to gather up powerful individuals capable of manipulating their Ether (with his guidance) and form the first guild which fought back the monstrosities and took the Orochi Isles back.
The Orochi Islanders powers developed tenfold after the monstrosities were dealt with.
Mages (Being capable of manipulating either their Ether or the surrounding Mana) made up for the better part of the population. But Sages (Those capable of manipulating both their Ether and Mana just as Torrikkusatu did) were becoming more prevalent also.
There were even new breeds of casters known as Runies' and Runists' who were born with an abundance of Ether but had no connection to Mana.
Soon guilds began to pepper the Islands varying in power. These guilds and their members would act as a shield in case the monstrosities every came back.
And The Orochi Isles has been enjoying its peace ever since.
But only a fool would choose to believe that it would last much longer...